IMAGE DISPLAY OF IMAGE OUT OF RANGE AND MONITORING METHOD. BACKGROUND OF THE INVENTION 1. FIELD OF THE INVENTION The present invention relates to a monitor and more particularly to an out-of-range image display device and monitoring method. 2. BACKGROUND OF THE RELATED ART A monitor typically performs a series of signal processing operations such as, for example, digital sampling, scaling and the like for image signals of a predetermined format transmitted from a source, for example, a video card of a personal computer connected to the monitor. The monitor then displays the processed image signals on a screen. Large display devices are currently under development which employ current technology. Therefore, the monitor has progressed from a small monitor that uses a cathode ray tube to a digital system that employs a liquid crystal display (LCD) as a representative flat display device suitable for the large monitor. The display performance of the monitor is determined by its resolution, which is divided into SVGA (800x600), XGA (1024x768) and SXGA (1280x1024).
As shown in Figure 1, an image processing device of a monitor in the related art includes an A / D converter for converting analog R, G and B image signals transmitted from a video card into image signals 8-bit digital R, G and B in accordance with a predetermined sampling clock that is synchronized with a H-zinc horizontal synchronization signal controlled by a control signal from a microcomputer. A buffer 2 is additionally provided for temporarily storing them. digital R, G and B image signals in a frame unit, and a video scaling device 3 converts the digital R, G and B image signals produced from the A / D converter 1 into the signals in a frame unit that can be displayed in LCD modules. The converted image signals are stored in the frame buffer 2 and transmitted to correspond to an input synchronization signal of the LCD module. Finally, a microcomputer 4 recognizes an input image format in accordance with horizontal and vertical synchronization signals H-sinc and V-sinc transmitted from the video card, and sends the control signal to both the A / D converter 1 as to the video scale change device 3 so that the display corresponds to the corresponding format.
In operation, if the analog R, G and B image signals and vertical and horizontal synchronization signals are input from the video card, the micro computer 4 first recognizes the resolution of the input image signals, i.e. SVGA, XGA and SXGA through the use of horizontal / vertical synchronization signals. Then, the microcomputer 4 applies the control signal to adjust the sampling clock of the A / D converter 1 for the digital conversion. The sampling clock is adjusted to correspond to the resolution set by a user, in the case in which the resolution of the input image signals is lower than the resolution supported on the monitor, for example, when the resolution of the monitor is XGA (1024 x 768) and the resolution of the input image signals is XGA or VGA. In response to the control signal, the A / D converter 1 generates the 95 MHz sampling clock to sample the XGA image signals to correspond to the horizontal synchronization signal. It also performs digital sampling for the input image signals and sends the 8-bit digital R, G and B image signals. At the same time, the A / D converter 1 sends a Dot Clock to recognize the signal of the video scaling device 3. The video scaling device 3 then stores the output of the A / D converter 1 in a unit of paintings, corresponding to the XGA resolution in the frame buffer 2, and sends the stored output to the LCD module, in accordance with the control signal of the microcomputer 4. The LCD module recognizes the digital R, G and B image signals of 8 bits sent from the video scale change device 3 in accordance with a data validation signal D / E and an external clock, and displays the 10 image signals to correspond to the signals of
• horizontal / vertical synchronization. However, when the resolution of the monitor is XGA and the resolution of the input image signals is SXGA, thus exceeding the display performance of the monitor, it is
15 requires a sampling clock speed of 135 MHz to convert SXGA image signals into digital signals. When the monitor has an XGA resolution, it can generate only a maximum sampling clock speed of 100 20 MHZ. Therefore, it can not display the input image signals on the screen, and displays the "out of range" on the screen (OSD). Since the monitor of the related art can not display the entered image when the image signals entered are outside the range of the monitor, a problem arises insofar as the monitor must be replaced by a new monitor that supports the mode of input image so that a user can see the corresponding image. The above references are incorporated herein by reference where it is appropriate for teachings of details, features and / or alternative or additional techniques. SUMMARY OF THE INVENTION An object of the present invention is to solve at least the aforementioned problems and / or disadvantages to provide at least the advantages described below. Another object of the present invention is to provide an out-of-range image display device and a method for a monitor capable of achieving normal display even when the resolution of the input image signals exceeds the resolution supported on the monitor. Another object of the present invention is to provide a device and method for displaying video data having a first format on a monitor having a second format. To achieve these objects and other advantages in whole or in part, an image display device outside the monitor range is provided, which includes an A / D converter for converting analog image signals into digital image signals composed of even pixels, odd pixels, and odd / even pixels in accordance with a sampling clock set by a control signal. A retarder for delaying a horizontal synchronization signal for a predetermined time; a switch for selecting one of the horizontal synchronization signal delayed by the time predetermined by the retarder and a normal horizontal synchronization signal for the purpose of generating the sampling clock of the A / D converter in accordance with a switching signal; a memory for temporarily storing the digital image signals in a frame unit; a video scaling device for storing even and odd pixels of digital picture signals produced from the A / D converter in memory in order to thereby build a frame and transmit the stored output to correspond with a signal input timing of a display module; and a microcomputer to produce the switching signal to switch the switch in synchronization with the vertical synchronization signal, if the resolution of the input image is higher than the resolution supported on the monitor and while sending the control signal to adjust the sampling clock of the A / D converter to the half of a normal sampling clock. To achieve these objects and other advantages in whole or in part, an out-of-range image display method is additionally provided, which includes determining whether the external input image signals are outside the range of the monitor; if the resolution of the external input image is outside the range of the monitor, odd or even 5 odd pixels are sampled for each of the image signals input before and after the input of a vertical synchronization signal; and forming each frame with the even and odd pixels sampled in the image signals input before and after the input of the vertical synchronization signal 10 and displaying the frame. To achieve the objects described above of the present invention in whole or in part, an image display device including an A / D converter for converting image signals of a first format into image signals of a second format is offered. , a pixel switch that divides the digital image signal
# in a plurality of first pixels and a plurality of second pixels, a delay circuit for delaying a horizontal synchronization signal during a prescribed period of time, a switch for selecting one of the horizontal synchronization signal and a horizontal synchronization signal delayed in accordance with a switching signal, a video scaling device that forms a frame from at least one of the first pixel and second pixel of the digital image signals sent from the pixel switch. In order to achieve the objects described above of the present invention in whole or in part, a method for displaying images on a monitor including the determination of whether the resolution of signals from external input images exceeds the resolution of the monitor, adjusting a clock is offered. sample, sample odd or even pixels for each of the image signals inputted before and after the input of a vertical synchronization signal, and construct each frame by employing at least one of the even and odd pixels sampled in the Image signals input before and after the vertical synchronization signal input and display the frame. Advantages, objects, and additional features of the invention will be presented in part in the following description, in part they will be apparent to those of ordinary skill in the art upon examination of the present document, or they may be learned by practicing the invention. The objects and advantages of the invention can be achieved as is particularly indicated in the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in detail with reference to the following drawings in which similar reference numerals refer to similar elements, where: Figure 1 is a block diagram illustrating the configuration of a processing device image of a monitor in the related art; Figure 2 is a block diagram illustrating the configuration of an out-of-range image display device of a monitor in accordance with a preferred embent of the present invention; Figure 3 is a flow diagram illustrating an out-of-range image display method of a monitor in accordance with a preferred embent of the present invention; Figure 4 is a timing diagram illustrating the waveforms of the horizontal synchronization signal and the sampling clock in accordance with a preferred embent of the invention. DETAILED DESCRIPTION OF PREFERRED MODALITIES The configuration and operation of an out-of-range image display device and method of a monitor in accordance with the integrated and widely described according to the present invention will be described below with reference to Figures 2, 3 and 4 With reference to Figure 2, an out-of-range image display device of a monitor in accordance with the preferred embent includes an A / D converter 11 for converting analog R, G and B image signals transmitted from a card of video in 8-bit digital R, G, and B image signals. The digital R, G, and B image signals are preferably composed of even pixels, odd pixels, and odd / even pixels of
% compliance with a sampling clock set by a control signal 5 of a control circuit 17, such as a microcomputer. Then, a delay circuit 12 delays a horizontal synchronization signal for a prescribed period of time, and a switch 13 selects one of the signal from
• 10 delayed horizontal synchronization and the normal horizontal synchronization signal. The switch 13 transmits the selected signal as a timing signal to generate the sampling clock of the A / D converter 11 in accordance with a control signal in the microcomputer 15 17. A pixel switch 14 is further provided to produce the even pixels and odd pixels of the R-image signals8 bits digital G, and B that are sent sequentially from the A / D converter 11, to each 20 path in accordance with a control signal of the microcomputer 17. A video scaling device 16 stores the pixels odd and even signals of 8-bit digital R, G, and B images sent to each path through the pixel switch 14 to 25 constitute a frame in the frame buffer 15, which temporarily stores the image signals R , G and B digital in a unit of tables. The video scaling device 16 then transmits the stored image signals to correspond with an LCD module signal input timing 5. The microcomputer 17 recognizes the resolution of the entered image in accordance with the horizontal and vertical synchronization signals transmitted from the video card, and if the resolution of the entered image is greater than the resolution supported on the monitor, it sends the signal of
% control for switching the switch 13 and the pixel switch 14 in synchronization with the vertical synchronization signal. At the same time, it sends a control signal to adjust the sampling clock of the A / D converter 11 to the half of a normal sampling clock. Next, an out-of-range image display method of a monitor in accordance with a preferred embodiment of the present invention will be described under the above construction scheme. With reference to Figure 3, if the analog R, G, and B image signals and the horizontal and vertical synchronization signals are input from the video card, the microcomputer 17 recognizes the resolution of the image signals of input, that is, 25 SVGA, XGA or SXGA through the use of horizontal / vertical synchronization signals (step S31). Then, the microcomputer 17 determines whether the resolution of the input image signals is more than the resolution of the
% resolution supported on the monitor (step S32). 5 It is determined that the resolution of the input image signals is higher than the resolution supported on the monitor, for example, if the monitor resolution is XGA (1024 x 768) and the resolution of the input image signals is SXGA (1280 x 1024), the microcomputer 17 sends 10 the control signal to the A / D converter 11 and sets the clock
• Sampling at half a normal sampling clock of 135 MHz that is required to convert the SXGA image to the digital signals, that is, the 67.5 MHz clock (step S33). Next, the A / D converter 11 samples the even pixels of the input image to form a first frame, in accordance with the sampling clock of 67.5 MHz, synchronized with the horizontal synchronization signal in an original state, as shown in "(a)" in Fig. 4 and 20 converts the input image signals into the 8-bit digital R ', G', and B 'image signals. If the vertical synchronization signal is input, the A / D converter 11 performs sampling for the odd pixels of the entered image in order to form a
25 second frame, in accordance with 67.5 MHz sampling clock synchronized with the horizontal synchronization signal for a set time delay, as shown in "(b)" in Figure 4 and converts the input signals into the signals of 8"digital R", G "and B" image (step S34) At this time, if the image signals for constructing the first frame are inputted, the microcomputer 17 controls the switch 13 under the output of the switch and input the horizontal synchronization signal in the original state to the 10 A / D converter 11. • If the vertical synchronization signal is input and the image signals to build the second frame are inputted later, the microcomputer 17 controls the switch 13 under the output of switching signal e 15 the A / D converter 11 enters the delayed horizontal synchronization signal which is delayed in the retarder 12 for the prescribed time required to sample the odd pixels, for example, during the 67.5 MHz sampling clock half. 20 Since the pixel switch 14 and the switch 13 switch in accordance with the same switching signal, the pixel switch 14 transmits the signals of image R ', G', and B ', and the image signals R ", G", and B "to the video scaling device 16 through each path 25 of the image signal. The video scaling device 16 stores the image signals R ', G' and B 'in the memory corresponding to the even pixels in the frame buffer 15 and the image signals R ", G" and B "in the memory corresponding to the odd pixels in the frame buffer 15, in such a way as to form a frame, and send the formed frame to the LCD module, and therefore display the output (step S35)., for a normal display, sampling only for the even pixels in the image corresponding to the first frame of the image corresponding to two frames and only for the odd pixels in the image corresponding to the second frame is carried out to form a picture, thus visualizing the picture. The two frames are then synthesized in the normal display process to form the frame, but a user who is watching can not detect the abnormal state of the screen due to the luminous persistence effect of the LCD screen, as it appears in a normal display. On the other hand, if the resolution of the input image signals is below the resolution supported on the monitor, for example, if the resolution of the input image signals is XGA (1024 x 768), then the converter A / D 11 performs sampling for the input image with the 95 MHz sampling clock corresponding to the resolution and converts the input image to the 8-bit digital image signals (step S36). The microcomputer 17 then adjusts the sampling clock of the A / D converter 11 at 95 MHz in accordance with the control signal, and controls the switch 13 in accordance with the output of the switching signal. The horizontal synchronization signal is thus entered in the original state to the A / D converter 11, independently of the input and of the vertical synchronization signal. Finally, each frame is formed with the digital image signals sampled in a sequential order and displayed through the LCD module (step S37). As is evident from the foregoing, an out-of-range image display device and method of a monitor in accordance with the present invention can achieve a normal display even in the case in which the resolution of the input picture signals exceeds the resolution supported on the monitor currently used, thus removing the problem of changing the monitor and improving the reliability of the user's product. The above embodiments and advantages are presented only by way of example and are not intended to limit the present invention. The teaching of the present invention can be easily applied to other types of apparatus. The description of the present invention is for illustrative purposes only and is not intended to limit the scope of the claims. Many alternatives, modifications and variations will be apparent to experts in the field. In the claims, the media clauses-more-functions
* are intended to cover the structures described here by performing the indicated function and not only structural equivalents but also equivalent structures.
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